Okay, this may take a bit but bear with me.

I've actually given talks about this at various conferences and conventions over the years, and it's always an interesting interaction with the audience. One of the first questions I ask is how many men have used a line. Pretty much all hands go up. Then I ask the women how many of them have had a line used on them. Same number of hands go up. Then I ask the men how many times their line has worked, and most of them raise their hands. When I ask the women the reverse question, almost none of their hands grow up. Which is almost always a surprise to the men.

The problem with "lines" in general is about power dynamics. A line is a dominant statement made toward a defensive person. It puts the recipient on guard and is almost always an uncomfortable approach. Men are so used to being dominant in social interactions that the vast majority are simply unaware of how their lines impact women.

In other worse, stop using lines. Period. Full stop. They aren't original, they aren't clever, and they put the object of your interest on the defensive.

With that said, there is one approach that actually works very well because it reverses the power dynamic. Here it is: "Hello. My name is [your name]. Can I buy you a drink?" Or a coffee, or a muffin, or such. Just make sure it is a small value item.

Here's what it works. First, you have introduced yourself, which expresses interest and doesn't demand reciprocation (as in, "Hi, what's your name?" which is the reverse dynamic). Second, you have confirmed your interest by offering an object of value.

And thirdly, the power now rests with the recipient. They have three basic responses that they can choose from. 1) Introduce themselves and accept the offer, 2) Politely decline the offer, or 3) Make a counter-offer (as in, "How about dinner?" or "Would you like to split something?" etc.) based on their mutual interest.

And I have seen this approach work time and time again. It's how I met the now Mrs. Winterlight years ago (I offered to buy her an ice cream), in fact.

TL;dr: "Lines" don't work, being nice does.